A pair of earthquakes with an epicenter outside of Quebec, Canada have rattled northern Maine, with the most recent earthquake striking at 7:30 pm last night about 6 miles west-southwest of La Pocatière, Canada. La Pocatière is a town in the Kamouraska Regional County Municipality in the Bas-Saint-Laurent region of Quebec, Canada; the epicenter of the quake was located on the bank of the St. Lawrence River. Five days earlier on July 1, an earthquake also struck on the opposite bank of the St. Lawrence River at about 5:30 pm in the evening. Both earthquakes were relatively weak and were rated by USGS as a magnitude 2.3 event.
While not famous for their earthquakes, Maine does get them from time to time. On April 24, an earthquake struck in central Maine, the 6th such earthquake to strike the Dirigo state this year. The magnitude 2.5 event had an epicenter about 3 miles south of Sebec, Maine; the earthquake’s epicenter had a depth of 3.3 miles. While there’s no report of any damage, more than a dozen people used USGS’s “Did you feel it?” reporting tool to report they felt the earthquake.
Earlier that month, on April 2, a magnitude 2.0 earthquake struck about 7 miles southeast of Waterville, near the Winslow-China town line. On March 8, a magnitude 2.1 earthquake struck about 2 miles north of Tunk Lake in eastern Hancock County. On February 12, a magnitude 2.4 earthquake struck 12 miles west of Houlton; some locals reported feeling shaking then. On February 4, a magnitude 2.9 event was widely felt in the Bethel area of western Maine, 8 miles from the epicenter in Gorham, New Hampshire. People up to 25 miles away from the epicenter of that earthquake felt it in Maine. Two earthquakes of a 2.0 magnitude hit on January 17 ; one was 2 miles west of Springvale, the other was about 1/2 mile south of Springvale.
The strongest earthquake to strike Maine in the last 10 years was a magnitude 4.5 event on October 16, 2012 in East Waterboro, about 13 miles northwest of Saco.
According to the Maine Geological Survey with the Department of Conservation, seismic activity in Maine is typical of the Appalachian region of northeastern North America. “There is a low but steady rate of earthquake occurrence,” they report, adding that “The earthquakes are presumably caused by modern stress being released occasionally along zones of weakness in the earth’s crust, but a more specific cause for the earthquake activity is not known.”
There have been other areas of earthquakes in eastern North America that USGS has been tracking too. In recent days, there has been a series of earthquakes in Missouri, Tennessee, and an unusually long-duration swarm event in South Carolina. However, due to the distance between all of the earthquake events, none are believed to be related to the other.